The technical field of this invention is semiconductor processing workpiece supports having sensory subsystems to detect the presents of wafers or other semiconductor workpieces therein.
In the production of semiconductor wafers and other semiconductor a articles and workpieces it is desirable to automate the production to varying degrees. If power is lost or if there is a malfunction in the controller or related functions, then the control system may not have information indicating whether a machine has a wafer or other semiconductor workpiece present. Accordingly, it is desirable to have means for determining whether a wafer is present within a processing station without requiring manual inspection.
Any wafer detection system must be robust to stand up to the oftentimes harsh chemicals and vapors present in processing semiconductors. Thus there is a need for improved subsystems for use in semiconductor wafer support heads which allows for reliable detection of the presence or absence of a wafer therein.